1. Technical Field
This invention relates to methods and devices that visualize three-dimensional graphics data, and, more particularly, to a method and apparatus for generating at high speed an isosurface from three-dimensional scalar data of an object body.
2. Description of the Prior Art
Scientific and technological calculation for three-dimensional object bodies (volumes) has an increasing area of application, such as medical measurement by a CT scanner and the numerical analysis of temperature and stress distribution encountered in the design of a personal computer enclosure. Typically, the three-dimensional object body is represented by volume data consisting of a set of multiple grid points. Each of the grid points has an associated scalar value determined by calculation. Accordingly, we must discuss the problem of representing at high speed the resulting three-dimensional scalar field on a display.
One representation technique for such three-dimensional scalar fields implements isosurfaces, which are surfaces composed of a set of points having the same scalar value. Representation by isosurfaces may be said to be an effective technique for representing three-dimensional scalar fields at high speed.
Existing techniques for generating isosurfaces include, for example, the following:
(1) representation by polygon approximation;
(2) representation by self-proliferating generation.